Vehicle travel control apparatus

Abstract

A vehicle travel control apparatus including an object detector, a yaw-rate detector, a vehicle speed detector, a movement path estimator, a preceding vehicle assignment device, a travel controller, a still object determination device, and a stable-movement-state determination device, wherein the preceding vehicle assignment device avoids assigning the object as the preceding vehicle, or assigns the object as the preceding vehicle after waiting for a predetermined time, when: the present vehicle performs the follow-travel control targeting the preceding vehicle; the object detected at a position between the preceding vehicle and the present vehicle is determined to be the still object by the still object determination device; and the present vehicle is determined to be in the stable-movement-state by the stable-movement-state determination device.

1. A vehicle travel control apparatus comprising:
 an object detector which detects an object that exists in an advancing direction of a present vehicle; 
 a yaw-rate detector which detects the yaw-rate of the present vehicle; 
 a vehicle speed detector which detects the speed of the present vehicle; 
 a movement path estimator which estimates the movement path of the present vehicle, based on the output of the yaw-rate detector and the output of the vehicle speed detector; 
 a preceding vehicle assignment device which assigns the object as a preceding vehicle; 
 a travel controller which performs a follow-travel control targeting the preceding vehicle; 
 a still object determination device which determines whether the object detected by the object detector is a still object; and 
 a stable-movement-state determination device which determines whether the present vehicle is, in a stable-movement-state, based on the output of the yaw-rate detector, wherein the preceding vehicle assignment device maintains the previous preceding vehicle assignment when: 
 the present vehicle performs the follow-travel control targeting the preceding vehicle; 
 the object detected at a position between the preceding vehicle and the present vehicle is determined to be the still object by the still object determination device; 
 the present vehicle is determined to be in the stable-movement-state by the stable-movement-state determination device; and 
 the stable-movement-state determination device determines that the present vehicle is in the stable-movement-state, when the absolute value of the integral value of the yaw-rate over a predetermined period is equal to or less than a predetermined value. 
 
     
     
       2. The vehicle travel control apparatus according to  claim 1 , wherein
 when:
 the present vehicle is performing the follow-travel control targeting the preceding vehicle by the travel controller; 
 the object detected at a position between the preceding vehicle and the present vehicle is determined not to be a still object by the still object determination device; and 
 the present vehicle is determined to be in the stable-movement-state by the stable-movement-state determination device, 
 
 the preceding vehicle assignment device assigns the object determined not to be a still object as the preceding vehicle. 
 
     
     
       3. The vehicle travel control apparatus according to  claim 1 , wherein
 when:
 the present vehicle is performing the follow-travel control targeting the preceding vehicle by the travel controller; and 
 the present vehicle is determined to be in a lane-changing-state by the stable-movement-state determination device, 
 
 the preceding vehicle assignment device assigns the object detected between the preceding vehicle and the present vehicle as the preceding vehicle. 
 
     
     
       4. The vehicle travel control apparatus according to  claim 1 , wherein
 when:
 the present vehicle is performing the follow-travel control targeting the preceding vehicle by the travel controller; and 
 the present vehicle is determined to be in an unstable state by the stable-movement-state determination device, 
 
 the preceding vehicle assignment device does not assign the object detected between the preceding vehicle and the present vehicle as the preceding vehicle. 
 
     
     
       5. A vehicle travel control apparatus comprising;
 an object detector which detects an object that exists in an advancing direction of a present vehicle; 
 a yaw-rate detector which detects the yaw-rate of the present vehicle; 
 a vehicle speed detector which detects the speed of the present vehicle; 
 a movement path estimator which estimates the movement path of the present vehicle, based on the output of the yaw-rate detector and the output of the vehicle speed detector; 
 a preceding vehicle assignment device which assigns the object as a preceding vehicle; 
 a travel controller which performs a follow-travel control targeting the preceding vehicle; 
 a still object determination device which determines whether the object detected by the object detector is a still object; and 
 a stable-movement-state determination device which determines whether the present vehicle is in a stable-movement-state, based on the output of the yaw-rate detector, wherein the preceding vehicle assignment device maintains the previous preceding vehicle assignment when: 
 the present vehicle performs the follow-travel control targeting the preceding vehicle; 
 the object detected at a position between the preceding vehicle and the present vehicle is determined to be the still object by the still object determination device; 
 the present vehicle is determined to be in the stable-movement-state by the stable-movement-state determination device; and 
 the stable-movement-state determination device determines that the present vehicle is in a stable-movement-state, when the absolute value of a lateral movement amount of the present vehicle in a predetermined period, calculated based on the yaw-rate and the speed of the present vehicle, is equal to or less than a predetermined value. 
 
     
     
       6. The vehicle travel control apparatus according to  claim 5 , wherein
 when:
 the present vehicle is performing the follow-travel control targeting the preceding vehicle by the travel controller; 
 the object detected at a position between the preceding vehicle and the present vehicle is determined not to be a still object by the still object determination device; and 
 the present vehicle is determined to be in the stable-movement-state by the stable-movement-state determination device, 
 
 the preceding vehicle assignment device assigns the object determined not to be a still object as the preceding vehicle. 
 
     
     
       7. The vehicle travel control apparatus according to  claim 5 , wherein
 when:
 the present vehicle is performing the follow-travel control targeting the preceding vehicle by the travel controller; and 
 the present vehicle is determined to be in a lane-changing-state by the stable-movement-state determination device, 
 
 the preceding vehicle assignment device assigns the object detected between the preceding vehicle and the present vehicle as the preceding vehicle. 
 
     
     
       8. The vehicle travel control apparatus according to  claim 5 , wherein
 when:
 the present vehicle is performing the follow-travel control targeting the preceding vehicle by the travel controller; and 
 the present vehicle is determined to be in an unstable state by the stable-movement-state determination device, 
 
 the preceding vehicle assignment device does not assign the object detected between the preceding vehicle and the present vehicle as the preceding vehicle.